1. Field of the Invention
The present invention relates generally to an improved probe for a composite analyzer tester for nondestructively testing and analyzing materials, and more particularly pertains to an improved probe for a composite analyzer tester for nondestructively analyzing the physical properties and gaging the thickness of advanced graphite-resin composite materials. Such graphite-resin composite materials are being utilized with a greater frequency of application in the construction of airplane components, such as for the aircraft skin and in other substructural components thereof.
2. Discussion of the Prior Art
The nondestructive testing of advanced fiber-matrix materials, such as graphite-resin composite materials and components, has been developed to provide a high level of assurance of the quality and structural integrity of such materials and components. The individual fiber and matrix material components that make up such a composite are often of non-uniform quality and moreover are laminated in different and varied patterns. Additionally, fabricators can be expected to make occasional human errors in the number and spacing of plies in the layup. Slight changes in curing cycles and rates of heating can also have major effects on mechanical properties, but no obvious effect on the visual appearance of the finished parts. In general, the deviation in properties for composite materials on multiple tests is far greater than considered acceptable for established metal technology. Refined and improved nondestructive testing apparatus and methods must be developed to allow inspection to establish, with greater assurance, the exact quality of the part under surveillance.
Many individual inspection, testing and analysis techniques have been developed for such fiber-matrix materials, such as by acoustic emission, radiographic testing, ultrasonic testing, magnetic induction testing, electrical conductivity testing, testing by liquid penetrants, thermal infrared testing, and by visual inspections thereof.
Related patent application for a Composite Analyzer Tester U.S. Ser. No. 895,789, filed Aug. 12, 1986, commonly assigned herewith, discloses a composite analyzer tester instrument having three separate probes, a magnetic induction probe, an ultrasonic pulse-echo probe, and an eddy current probe, which are used in succession to take four separate measurements of different properties of a test material. An instrument of this type requires the expense of three separate different probes, and requires the user to accurately place all three probes at the same location on the test material in successive measurements.